Hesitation

I've been excercising the B more and more since I got it running 6 weeks ago. Just ran Seafoam through it and took it out to, as JDW says, "run the crap out of it." After about two minutes at highway speed, it hesitates and misses. It hasn't shut down, but close. At first, the problem was only in forth gear, so I thought it might be the vacuum advance. Last time out, though, it continued after downshifting to third gear. At city speeds, the car runs fine.

What is happening? It sounds timing related to a newbie like me. Can cleaning the engine with Seafoam alter the timing, or is this just a coincidence? Thanks in advance for your help.

Craig Kubiak
'79B

P.S. Happy Fathers' Day to you Dads out there!

Coincidental, change your condensor!! It is cheap and easy and it is one part that is effected by heat!!

See if it does it quicker on an up hill run. If so check your gas filter for being clogged.

Sorry, I didn't mention that I've got electronic ignition. I changed out the cap, rotor, wire set and plugs when I woke it up. I'll try JDW's test to see if it might be the fuel filter. If not, is there anything else to check on the dizzy?

The amount of side wiggle of the shaft, but that is not your problem.

Mine (79 with HS-4s) did this; turned out to be float settings - at high speeds, it would starve after a little while. I made sure the float hinge pins were tight, set both floats slightly higher than the listed 1/8", problem went away.

May not completely apply if you are running the ZS, but it is a possibility.

Not likely that timing could cause a miss. Ignition possibly if something is heating up, but my bet is fuel. If you have the original ZS carb, check that the mixture is right, the float level is set at something over the 5/8" spec, and if you have a strainer on the bottom of the float valve, that it isn't clogged. Fuel pump putting out OK?